This is an application for a supplement to an ongoing program project. The subtitles of the specific projects proposed in this application describe the proposed research as follows: 1. Hypertension caused by stimulation of renal sympathetic nerves. 2. Studies on the regulation of aldosterone secretion. 3. Studies on the interlocking relationships among the four important controls of body fluid volumes and electrolytes: (A) The aldosterone feedback control system, (B) The antidiuretic hormone and thirst feedback control system, (C) The volume receptor feedback control system, and (D) The arterial pressure-renal diuretic feedback control system. 4. Water hypertension: Feedback control of body water volume as a basic mechanism of arterial pressure control. 5. Servocontrol of arterial pressure by application of diffuse pressure to the outside of the kidney. 6. Regulation of the microcirculation: Blood and Lymph. 7. Further development of an overall computer model of circulatory function. 8. Investigation of new predictions from basic theoretical analyses, specifically predictions that have been made from the overall computer analysis of circulatory function.